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91.
Heterosexual co-transmission of hepatitis C virus (HCV) and human immunodeficiency virus (HIV). 总被引:10,自引:0,他引:10
M E Eyster H J Alter L M Aledort S Quan A Hatzakis J J Goedert 《Annals of internal medicine》1991,115(10):764-768
OBJECTIVES: To determine the prevalence of antibodies to hepatitis C virus (HCV) in female sexual partners of multitransfused men with hemophilia and to compare the frequency of transmission of HCV and human immunodeficiency virus (HIV). STUDY DESIGN: Cross-sectional measurement of HCV and HIV antibodies. SETTING: Ten hemophilia treatment centers. PATIENTS: A total of 234 female sexual partners of 231 multitransfused men with hemophilia. MEASUREMENTS AND MAIN RESULTS: The prevalence of antibodies to HCV (anti-HCV) among female sexual partners of HCV-positive men was 5 of 194 (2.6%). Anti-HIV prevalence among female sexual partners of HIV-positive men was 25 of 196 (12.8%). Five (3%) of the 164 female sexual partners of HIV-positive/HCV-positive men were infected with HCV compared with none of the 30 female sexual partners of HIV-negative/HCV-positive men. Twenty-one (13%) of the 164 female sexual partners of HIV-positive/HCV-positive men were infected with HIV compared with 4 (13%) of 32 female sexual partners of HIV-positive/HCV-indeterminate men. The co-infected men were five times more likely to transmit both viruses than would be expected by chance (P = 0.01). When a single virus was transmitted to a female sexual partner, it was more often HIV than HCV (18 of 164 compared with 2 of 164, P = 0.001; odds ratio, 8.5; 95% Cl, 2.2 to 33.1). CONCLUSIONS: The higher prevalence of HCV in female sexual partners of men with hemophilia than in blood donor and other low-risk groups suggests that there is a low level of sexual transmission. Male to female sexual transmission of HCV is less efficient than that of HIV. The frequency of HCV transmission to sexual partners is five times higher when HIV is also transmitted, suggesting that HIV may be a cofactor for the sexual transmission of HCV. 相似文献
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93.
Interleukin-11 stimulates multilineage progenitors, but not stem cells, in murine and human long-term marrow cultures 总被引:3,自引:0,他引:3
Interleukin-11 (IL-11) is a bone marrow microenvironment-derived growth factor with pleiotropic effects on a variety of hematopoietic cells. To more accurately assess the effects of IL-11 on stem and progenitor compartments within the hematopoietic microenvironment (HM), we added recombinant human (rh) IL-11 to human and murine long-term bone marrow cultures (LTMC) and analyzed primitive (high proliferative potential- colony forming cells [HPP-CFC], long-term culture-initiating cells [LTC- IC], and long-term reconstituting stem cells) and progenitor (day 12 colony forming unit-spleen [CFU-S12], colony forming unit-megakaryocyte [CFU-Mk] and colony forming unit-granulocyte/macrophage [CFU-GM]) compartments throughout the duration of the cultures. rhIL-11 (100 ng/mL) added twice weekly resulted in significantly increased nonadherent (NA) cellularity, CFU-GM, and CFU-Mk production in human LTMC. Addition of rhIL-11 to murine LTMC was associated with a 5- to 40- fold increase in CFU-GM and a four- to 20-fold increase in day 12 CFU-S in NA cells. However, IL-11 had no significant effect on total HPP-CFC concentration and decreased the size of the more primitive stem/progenitor compartment as evidenced by both decreased LTC-IC frequency in human LTMC and decreased frequency of long-term reconstituting stem cells in murine LTMC. These data suggest that IL-11 may increase commitment of stem cells into a multipotential progenitor compartment. 相似文献
94.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
95.
目的 观察肢带型肌营养不良的MRI表现。方法 回顾性分析7例经临床及病理检查确诊为肢带型肌营养不良患者的MRI资料,观察双侧大腿肌群脂肪沉积与炎性水肿情况,采用4分法进行评价。并进行统计学分析。结果 肢带型肌营养不良患者大腿肌群MRI均可见脂质沉积和炎性水肿性改变。不同肌肉间脂肪沉积(χ2=75.596,P<0.01)与炎性水肿差异均有统计学意义(χ2=41.368,P<0.01),双侧大腿肌群间脂肪沉积与炎性水肿差异均无统计学意义(P均>0.05)。结论 肢带型肌营养不良患者大腿肌群MRI信号特点及分布具有一定特征,MR检查有助于疾病的诊断。 相似文献
96.
目的对比高黏度与低黏度骨水泥经皮椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩性骨折(OVCF)的疗效差异。方法将2013年3月至2014年9月高要市人民医院收治的60例OVCF患者采用随机抽签法分为低黏度组(低黏度骨水泥PKP治疗)和高黏度组(高黏度骨水泥PKP治疗),每组各30例。对比两组手术前后伤椎椎体高度和后凸Cobb角;采用视觉模拟量表(VAS)评分、Oswestry功能障碍指数(ODI)、36项健康调查简表(SF-36)评分对患者疼痛程度、功能障碍和生活质量等主观感受进行评价;统计骨水泥渗漏、近期肺栓塞等并发症发生情况。结果低黏度组和高黏度组骨水泥注入量分别为(3.1±0.6)m L和(3.6±0.8)m L,两组比较,差异有统计学意义(P0.05)。术后随访3~6个月(平均4个月),两组术后1 d、3个月VAS评分、ODI、SF-36评分、伤椎椎体高度和后凸Cobb角均优于术前(P0.05),其中高黏度组术后1 d、3个月上述指标均优于低黏度组(P0.05)。低黏度组和高黏度组术后发生骨水泥渗漏、近期肺栓塞分别为6、2例和1、0例,两组并发症发生率比较,差异有统计学意义(P0.05)。结论与低黏度骨水泥比较,高黏度骨水泥PKP治疗OVCF近期疗效更为理想,骨水泥渗漏、近期肺栓塞等并发症发生率相对较低,值得临床推广应用。 相似文献
97.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。 相似文献
98.
Payal P. Khincha Ingrid M. Wentzensen Neelam Giri Blanche P. Alter Sharon A. Savage 《British journal of haematology》2014,165(3):349-357
Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome and telomere biology disorder characterized by dysplastic nails, reticular skin pigmentation and oral leucoplakia. Androgens are a standard therapeutic option for bone marrow failure in those patients with DC who are unable to undergo haematopoietic stem cell transplantation, but there are no systematic data on its use in those patients. We evaluated haematological response and side effects of androgen therapy in 16 patients with DC in our observational cohort study. Untreated DC patients served as controls. Seventy percent of treated DC patients had a haematological response with red blood cell and/or platelet transfusion independence. The expected age‐related decline in telomere length was noted in androgen‐treated patients. All treated DC patients had at least one significant lipid abnormality. Additional treatment‐related findings included a significant decrease in thyroid binding globulin, accelerated growth in pre‐pubertal children and splenic peliosis in two patients. Liver enzymes were elevated in both androgen‐treated and untreated patients, suggesting underlying liver involvement in DC. This study suggests that androgen therapy can be effectively used to treat bone marrow failure in DC, but that side effects need to be closely monitored. 相似文献
99.
100.